Procedure at MFB/CCTV crossings

Status
Not open for further replies.

w0033944

Member
Joined
23 Jul 2011
Messages
514
Location
Norfolk
I don't know whether the chap concerned is a member here, but I subscribe to this Youtube channel:

http://www.youtube.com/user/SteveDD1?feature=watch

Yesterday, he uploaded videos of some of the 4 and 6-track crossings of the ECML and ECML plus ex-Midland route, and, in two of them (Maxey and Conington), there was an incredibly brief road-open period, which I'm sure was shorter than the minimum road-open period for AHB crossings, and which, in both cases, saw the amber lights re-illuminating as he was either pulling forward towards the position of the barriers or about to do so. I appreciate that, at Maxey, there was some road traffic waiting on the far side (though in that case, the road closing procedure commenced when that road traffic was halfway across), but, at Conington, he was most likely the only vehicle waiting.

Can anyone with greater knowledge in, or experience of, signalling these types of crossings comment on the examples in the videos?
 
Sponsor Post - registered members do not see these adverts; click here to register, or click here to log in
R

RailUK Forums

Tomnick

Established Member
Joined
10 Jun 2005
Messages
5,491
As I understand it, the controls to ensure that the sequence at an AHB crossing isn't restarted for a second train within ten seconds of the barriers raising behind the first is to avoid the risk of motorists stalling (perhaps as a result of panic) if the amber light illuminates as they're pulling onto the crossing from a standing start. Perhaps there were concerns over congestion on the crossing in those initial few seconds too.

Obviously none of that would be a worry at a full-barrier crossing where the Signalman checks that the crossing is clear (locally or via CCTV) before being able to clear the protecting signal. In the videos taken at Maxey and Conington, there was obviously an opportunity to briefly raise the barriers between trains, to allow the waiting traffic to pass - once the traffic has entered the crossing, there's no problem with starting the sequence again to drop the barriers for the next train. If the chap in question had moved off in a timely manner, he'd have got across with no problem (note that it takes almost thirty seconds, no doubt on account of the 'length' of the crossing, for the exit barriers to lower).
 

w0033944

Member
Joined
23 Jul 2011
Messages
514
Location
Norfolk
Thanks Tomnick - that's my reading of the situation as well. My query mainly revolved around the thought that there may be a minimum road-open time for signalling staff to adhere to, similar to that built-in to AHB crossings. I timed the Maxey example at 5 seconds from barriers fully raised to amber light, half that of the minimum interval for an AHB installation.

Plus, what the hell was he doing stopping on the tracks at the end of the Conington video?:roll:
 

Tomnick

Established Member
Joined
10 Jun 2005
Messages
5,491
There's nothing that I'm aware of - in the past, I've seen the sequence restarted before the barriers had even fully raised!

I'd not watched the video all the way through (there's only so long a set of barriers can hold your attention for!), but yes, he does indeed stop on the crossing. Perhaps he's one of these folk who like to stop on the crossing to make sure there's nothing coming?
 

w0033944

Member
Joined
23 Jul 2011
Messages
514
Location
Norfolk
There's nothing that I'm aware of - in the past, I've seen the sequence restarted before the barriers had even fully raised!

Interesting - thanks.

I'd not watched the video all the way through (there's only so long a set of barriers can hold your attention for!), but yes, he does indeed stop on the crossing. Perhaps he's one of these folk who like to stop on the crossing to make sure there's nothing coming?

An idiot, in other words.<( I've never seen him do it in any of his previous videos.
 

GB

Established Member
Joined
16 Nov 2008
Messages
5,876
Location
Somewhere
Two other cars had crossed Maxey crossing in the time it had taken him to start moving and as already pointed out, if he wasn't fannying about so much he could have crossed both Maxey and Conington.
 

w0033944

Member
Joined
23 Jul 2011
Messages
514
Location
Norfolk
He has a habit of turning-off his engine at AHB crossings as well, and sometimes takes so long to get going and get across that I find myself wondering whether he's going to be just nosing across as the crossing reactivates one of these days.
 

Peter Mugridge

Veteran Member
Joined
8 Apr 2010
Messages
11,722
Location
Epsom
It's not one sequence - in the Conington one the clouds flick slightly just after the gates finish rising and immediately before the amber light comes on. So it does not show the actual time between sequences.

There are at least three other edit togethers in the same clip.
 

w0033944

Member
Joined
23 Jul 2011
Messages
514
Location
Norfolk
It's not one sequence - in the Conington one the clouds flick slightly just after the gates finish rising and immediately before the amber light comes on. So it does not show the actual time between sequences.

There are at least three other edit togethers in the same clip.

He certainly edits the clips, but I can't see one there. It was a breezy morning I suspect - the clouds are drifting but I don't see a jump or flick. What I suspect you're seeing is vibration when he starts his engine - he drives a van, and the body does vibrate a touch, hence shaking the camera.
 
Last edited:

Tomnick

Established Member
Joined
10 Jun 2005
Messages
5,491
I've read some of his captions in a bit more detail now:
...Manea Station level crossing half a mile away. An absurdity is that the crossing there must have closed 90 seconds before this one.
Network Rail add to this by closing the barriers too early. I was there waiting for 12 minutes altogether. The wait for the last train was 3 minutes, 39 seconds. For the HST it was 4 minutes, 18 seconds. This compares with a wait of just 23 seconds for the HST at Ufton Level Crossing.
I'd have thought that someone who spends so long observing the operation of level crossings would at least understand the difference between AHBs and full barrier crossings?
 

w0033944

Member
Joined
23 Jul 2011
Messages
514
Location
Norfolk
I've read some of his captions in a bit more detail now:


I'd have thought that someone who spends so long observing the operation of level crossings would at least understand the difference between AHBs and full barrier crossings?

He sent me a PM in Youtube thanking me for my comments and providing info. on how many crossings he videoed in the one day and that it took him most of Sunday to research which trains he'd filmed, and to edit and upload the videos. I took the opportunity in my reply to explain some of the procedure and the causes for this apparent imbalance was one of the things I covered. I'm sure, having read captions to previous videos he's shot, that he knows the difference but that, for whatever reason, to him the fact that both types are used on the British network seems odd. Mind you, I am dabbling in amateur psychology there.
 

GB

Established Member
Joined
16 Nov 2008
Messages
5,876
Location
Somewhere
He certainly edits the clips, but I can't see one there. It was a breezy morning I suspect - the clouds are drifting but I don't see a jump or flick. What I suspect you're seeing is vibration when he starts his engine - he drives a van, and the body does vibrate a touch, hence shaking the camera.

At about 2:00 there does seem to be a flick of some sort and the general exposure to the shot seems a little different.

One thing that does surprise me with connington is how quickly the red road lights extinguish vice angle of the barrier...doesn't look like 45 degrees.
 

w0033944

Member
Joined
23 Jul 2011
Messages
514
Location
Norfolk
Don't get me wrong - he edits most of his videos - it's just that I didn't think there was a cut at the point in the Conington video between the barriers raising and the amber lights coming back on (there are, of course, cuts elsewhere in it, including, as GB said, one at 2 minutes).
 

bluenoxid

Established Member
Joined
9 Feb 2008
Messages
2,210
Just watched the above. Rather bemused by the reversing back.

http://www.youtube.com/watch?v=gQ4bqEANVF0&feature=autoplay&list=ULKV8bGhm_CLY&playnext=1

The above crossing (Tredington) could do with its Black Boards replaced.

The little burst at the end of the sequence seems a bit worrying

http://www.youtube.com/watch?v=Dn0AloWIDnU&feature=autoplay&list=ULVTc7L_HYswQ&playnext=3

Here is another one that could do with the Black Boards Replacing

http://www.youtube.com/watch?v=h_r9TPk6iuU&feature=autoplay&list=ULDn0AloWIDnU&playnext=4
 

Tomnick

Established Member
Joined
10 Jun 2005
Messages
5,491
Another video from this guy, but this time are we looking at genuine signalling error? Barriers are descending as he approaches, but then raise again at 0.42.
There are a few reasons for barriers to be lowered without a train approaching - perhaps something that the S&T were doing? At one box I know, the (adjacent) barriers must be lowered before the trailing crossover can be reversed (as there are no signalled moves over the crossover - presumably this eliminates the risk of the crossing being overlooked when authorising a movement), which is sometimes necessary for the S&T or P-way to briefly work their magic. That's clearly not the case here, but I'm sure it causes some puzzled faces!
 
Status
Not open for further replies.

Top